Prince Charles and Prince Andrew
Prince Charles and Prince Andrew attend Christmas Day Church service at Church of St Mary Magdalene on Dec. 25, 2017 in King's Lynn, England. Getty Images/Chris Jackson

Prince Charles intentionally snubbed Prince Andrew during one event that caused the latter to be upset.

According to Katie Nicholl in her book “Harry: Life, Loss and Love,” the Prince of Wales left out the Duke of York for the Queen’s Diamond Jubilee celebration in 2012. Prince Charles streamlined the royal family by only inviting Camilla Parker Bowles, Prince William, Kate Middleton and Prince Harry by the Queen’s side.

“It is no secret that Charles wants a more streamlined Royal Family when he comes to reign,” Nicholl added.

However, the royal author added that Prince Philip would have not allowed it if he were just well enough to attend the event. The Duke of Edinburgh didn’t make it because he was suffering from ill health.

Prince Charles’ decision hurt a number of the royal family members, in particular, Prince Andrew, who wanted to be there.

“It did cause some ill-feeling among some members of the extended family, including Prince Andrew, who was particularly upset not to have been included,” Nicholl continued.

On the other hand, Prince Charles’ other siblings Princess Anne and Prince Edward were more accepting about the future king’s decision.

It is believed that Prince Charles did it because he considered Prince Andrew a liability. The Duke of York was involved in some controversies earning him the monikers “Randy Andy” and “Air Miles Andy.” At the time, the heir was determined to secure the longevity and future of the House of Windsor and Prince Andrew wasn't fit to be in the picture.

“Charles wanted a slimmed-down, value for money monarchy, with no embarrassing hangers-on,” Nicholl added, implying about Prince Andrew’s controversies.

Prince Andrew earned the "Air Miles Andy" nickname due to his outrageous travel expenses. The Duke usually travels with five officials, opts to fly in first-class chartered planes and stays in five-star hotels.

In addition, Prince Charles wasn’t supportive of Prince Andrew’s romance with Sarah Ferguson. In fact, according to Nicholl, his relationship with the Duchess of York “really riles” Prince Charles and only contributed to something that Prince William and Prince Harry’s father found unpalatable against Prince Andrew.

Princess Anne and Prince Philip also don’t approve of Ferguson for Prince Andrew. The Duke and Duchess of York have been divorced for over two decades but remain friends. They still spend time together, sparking rumors that they could have reconciled.